Is XEP 201 supported?

As always, the sources is the ultimate ( and only) documentation. I use only the thread element for messages of type "chat". There I try to have some consistency. Looking at http://www.xmpp.org/extensions/xep-0201.html#chat I think I come pretty close. The code explains it better than I do:

    # We must follow the thread...
    # There are several cases to deal with: Have thread page, have dialog?
    if {($thread ne "") && $config(chat,allow-multi-thread-per-jid)} {
 set chattoken [GetTokenFrom chat threadid $thread]
    } else {

 # Try to find a reasonable fallback for clients that fail here (Psi).
 # Find if we have registered any chat for this jid 2/3.
 set chattoken [GetTokenFrom chat jid [jlib::ESC $mjid2]*]
 if {$chattoken eq ""} {

     # Need to create a new thread ID.
     set thread [jlib::generateuuid]
 } else {
     variable $chattoken
     upvar 0 $chattoken chatstate

     set thread $chatstate(threadid)
 }
    }

and

    # Shall we allow multiple chat threads (and dialogs, tabs) per JID?
    set ::config(chat,allow-multi-thread-per-jid) 0

This is when messages are received. For starting chats I normally only allow a single thread per JID:

   # If we initiate a chat when already have one, keep same window.
    set ::config(chat,start-jid-same) 1